Traveling-grate furnace



Jan. 15, i924. 1,480,964

L. STEINMULLER TRAVELING GRATE FURNACE Filed Feb. 11. 1921 35W@ @gym fm @Hoang Patented dan. l5, 1924.

LEBRECHT STEINMLLER, or eunminnsnncn, .,anni/reim.iV j

'rnAvnLrnG-Gnarn nommen,

Application led February 11, 1921i Serial No'. 444,226,

Hungary, Sept. 29, 1919, Patent 77,331; Nor-V way, Sept. 24,1919, Patent 83,995; Belgium, Sept. 27, 1919, 282,476; Switzerland, Sept. 11, 1919, Patent 88,150; Holland, Oct. 25, 1919, Patent 7 ,328;Great Britain,-Sept. 25, 1919,1)atent 151,470; Italy, Oct. 1o, 1919, Patent 178,673 Sweden, lSept. 17, 1919, Fatent 54,214; `Finland, vGot. 4, 1919, Patent 8,052; Poland, March 3, 1920, application pending; Austria, Sept. 1, 1919, Patent 85,- 483; Denmark, Sept. 20, 1919, Patent 28,527; Czechoslovakia, Nov. 26, 1919, application pending; Spain, Sept. 29,1919, Patent No. 70,982), of which this is a specification,

The Vpresent invention relates to traveling grate furnaces and particularlyto furnaces of this type having a wallor lire bridge overhanging the grate adjacent its rear or discharge end, and having means designed and constructed to prevent the entrance of air into` the combustion space through the opening between the'grate proper and the lower end of the tire bridge. Means of the character indicated-have been heretofore designed or suggested andhave consisted usually in a plurality of movably suspended members hung from the fire bridge and having their lower ends in proximity to the upper surface of the bed of fuel and ash lyincr upon the grate.

' In application lSerial No. 444,227 tiled in the names ofiMax Gensch and myself as joint inventors, is disclosed and claimed a novel means designed and constructed to cause the formation of a bank of fuel substantially within the ash discharge opening of a traveling grate furnace of the type indicated which means comprises a plurality of suspended members individually operable andextending into the body of the fuel on the grate. These members so resist the passage of the fuel and ash through the Ydischarge opening that a considerable fuel bank is maintained in front of said' members,

which fuel bank, together with the mech-Y anical means for maintaining it, substantially closes the ash discharge opening, and

the resisting means is of such character that any air passing through the ash discharge opening into the combustion space is guided through the bank of fuel. As Vavresult, fnofree or uncombined oxygen may enter vthe combustion space throughl .said opening. Y The apparatus above described ha's'a'number 7 of important advantages fully brought .out

inthe specification-referred to.

The object of the presentinvention is to provide an improved'mechanism of this class provided with meansto cooperate'withjthe retarding .means tocause the retarding means to exert the desired pressure against the :fuel and ash in' front-ofthe same to .maintain the bank, land to decrease suddenly Vthis resisting'or counter pressurewhen the pressure of the ash becomes excessive because of the presence of` a clinker, to quickly release the clinker; and toquickly reapply the original counter pressure to the ash following, after the clinkerhas passed, so thattheY bank is maintained along the entire length of the retarding or bankingV device.V

The invention may have various embodiments several of which are illustrated in the accompanying drawings and are below de'- scribedV in detail.

In the drawings'z; Y

Figure 1 is a transverser section through the retarding device and fire bridge, show-V ing diagrammatically the position of the ire grate; y Y VFigure 2 is a similar view offa modified form ofthe invention; i Figure 3 is a similar view of a third form of the invention; l y y Y i ,Figure 4 is a section onr line 4--4fof Figure 3; and n Figure 5 is a transverse section through the furnace combustion space llooking toward the fuel retarding members.

As previously pointed out, the mechanism operates inrsuch manner that the fuel Yre- Vtarding member is opened rapidlyV (when it is necessary for it to open) so that the pieces ori lumps of clinker 'pass rapidly therethrough, whereupon the fuel retarding member closes again rapidly in order to interrupt leu the fuel retarding action for as short Va Y vary the closingaction `ofthe fuel retarding f member. The Weight maybe-adapted to roll Y along a track connected to the fuel retarding member, the track constituting in itself a constant weight rigidly secured to the retarding member. The trackway may be independently mounted, if desired, and operatively connected to the retarding member.

Referring to Figure l, a fuel retarding member is indicated at a it being understood that a plurality of such members are utilized, being pivotally hung from a common shaft l) which is in turn preferably supported upon the lower end of the transversely extending fire bridge c, which may be water cooled, if desired. The number of retardinggate members will vary with the width of the grate, as will be understood by those skilled in the art.

To each member a. is rigidly secured a trackway or lever d having a projection d which normally rests on a stop e preferably formed of a piece of angle iron. The trackway l may be formed in various ways to accommodate or support a rolling weight or ball It may be a tubular member or channel s laped. The inclination of the trackway d is such that, whenl the member a is in its normal position as shown, the rolling weight f rests at the outer end of the lever CZ thus exerting greatest turning moment on the member a and therefore causing said member to exert the greatest resistance or counterpressure against the layer of fuel carried forward by the traveling grate g. The fuel, which may be finely granulated material, is thus retarded so that it is completely consumed before discharge of the ash. ylf the pressure of a clinker against the member a is so great that the clinker must be discharged, the member ct' will swing back and raise ,the trackway Z so that the trackway CZ passes its horizontal position and assumes an opposite inclination to its normal position. During this movement the weight f will roll toward the left so that pressure on the member a is correspondingly lessened and consequently the member a can be easily and rapidly opened further under the pressure of the clinker, so that the member a opens sufficiently to discharge the clinker without offering material resistance thereto. o As soon as the clinker has passed beneath the member a the latter falls until the trackway d again passes its horizontal position, when the weight fwill roll to the right and thus suddenly increase the pressure on the mem-V bei` a and therefore accelerate the closing thereof and assist in holding the member a in its closed position.

In the modification illustrated in Figure 2, a trackway d2 is employed in the form of a double-armed lever pivotally supported upon the shaft h2. The trackway isy siniilarlyv provided with a rolling weight f. The member a is provided with a roller ,7c which engages one arm of the lever Z2 and the member a, the pressure tends to `close Y this member, in order to insure the closing thereof after the discharge of the clinker.

In themodification illustrated in Figures 3 and 4t the double armed lever or trackway d3 is of U-shape and at the front end embraces a roller c on the fuel retarding member a2, being closed at the rear by a cross piece y. In the guide so formed is mounted a weight f2 which is preferably constructed as shown in Figure 4.

The normal position is shown in full lines in Figure 8 where the Weight f2 is situated at the left hand side of the pivot of the 1ever or trackway, that is to say, close to and exerting pressure upon the fuel retarding member. llVhen the latter is swung out, as

shown in dotted lines, the weight f2 moves to the outer endV of the trackway, thus assisting the opening movement of the fuel retarding member.

Mounted upon the pivotal shaft m from which the double armed lever is suspended, beyond the end of the grate and outside of the furnace, is a hand wheel w by means of which the shaft x may be rotated in either direction without directly actuating the trackufay (Z3 mounted loosely on the shaft m. Secured upon the shaft 41:, however, is an arm s which is moved to the right or left according to the rotation of the shaft ai through the hand wheel tu. In the preferred construction, the retarding members a2 are relatively narrow, having in many instances greater length than width, and a sufficient number of these `members are suspended side by side from the shaft b2 to extend from'one edge of the fgrate to the other. An individual trackway (Z3 is provided for each member, and an indiif'idual operating arm s is provided for each trackway. The invention is not limited, however, to retarding members of any particular width.

In the position illustrated in full lines in Figure 3, the -arm s rests on the trackway da in such position that it increases the pressure of the mechanism against the retarding member Ca2. lf the shaft is rotated in a clockwise direction, the arm s will be moved to the right hand side of the shaft so that the weight of the arm s will tend to raise the fuel retarding member. By

further rotation of the hand wheel fw, the trackway or double-armed lever d3 may be swung in a clockwise direction, and the fuel retarding member a2 lifted to inoperative position, as shown in dotted lines. When turned in an anti-clockwise direction the fuel retarding member will be returned from the open position to its normal working position, as shown in full lines. Generally, however, and in the usual operation of the furnace, the hand wheel is turned so that `the arm s occupies an intermediate or neutral position and does not affect the operation of the weight mechanism.

To one skilled in the art the advantages of the invention will be apparent and it will also be obvious that additional modifications and variations of form may be employed without departing from the `spirit 1i and scope of the invention.

Having thus described the invention what is claimed as new and desired to be secured by Letters Patent is:

l. In a traveling grate furnace, the combination of the traveling grate with a `wall cr lire bridge overhanging the same and adjacent the discharge end thereof, the lower end of the bridge being spaced above the `grate to provide ample opening for the passage of ashes and clinkers, and means for maintaining a bank of fuel and ash on the grate, which means, together with the fuel bank substantially closes the said opening against the ingress of free oxygen into the combustion space and second means acting on said first means to cause the same to resist the passage of ash toward the discharge end of the grate with a variab-le force, the resisting force decreasing suddenly when said first means is moved by the ash to a predetermined point and increasing suddenly when said meansreaches said vpredetermined point in its return movement, whereby clinkers of relatively large size may be quickly discharged, and maximum pressure on the ash following the clinker quickly reapplied.

2, In a traveling grate furnace, the combination of the traveling grate and a fire bridge above the same adjacent its discharge end, the lower edge of the bridge being spaced alcoveV the grate to provide ample opening for `the passage of clinkers, and means for maintain-A ing a bank of fuel on the grate adjacent said wall, said means including a plurality of aligned swinging gate members, and said means,` together with the bank of fuel substantially closing said opening against the ingress of free oxygen into the combustion space, and means Vconnected to each gate member and designed and constructed to cause said gate member to resist the passage of ashes with a variable force.' said last mentioned means including a trackway mov- Y ably -supported vindependently of said gate member but connected thereto, and a weight movable `along saidV trackway, said kweight moving along theJ trackway in one direction when the gate memberl passes a predetermined point in its opening movement, to decrease theY pressure of the gate against the ash, and moving along this trackwayin the opposite directionk when the gate passes this point on its closing movement, to'increase suddenly the pressure of the gate against the ash. j c

3. In a traveling grate furnace, the comlcridge above the same adjacent its discharge end, the lower edge ofthe bridge being spaced wall, said means including a` lbination of theV traveling grate and'a fire which means, together` with the bank of fuel substantially closes said opening against the ingress of free oxygen into the combustion` space, and second means connected to each gate member to cause the same to resist the Vpassage of ashes with a variable kforce, said secondfmeans including a trackway pivotally supported vindependently of saidvgate member and pivotally connected thereto, and a VWeight movable along said trackway under the influence of gravity, said weight moving along the trackway in one direction when the gate member passes a predetermined pointV in its opening movement, to decrease the pressure of the gate member against the ash, and moving along the trackway in the opposite direction when the gate passes this Y point in its closing movement, to increase suddenly the rpressure of the gate against theash. n

' 4. In a traveling grate furnace, the combinationof the traveling grate, and a fire bridge above the vsaine adjacent its dischargeV end, theV lower edge of theV bridge` being spaced above the grate to providev ample opening for the passage ofclinkers, kof means for'maintaining a bank of fuel on the-grate adjacent saidwall, said means including a pluralityT of aligned and relatively movable suspendedgate members,which means, together with the bank of fuel substantially closes the said opening against the ingress of free oxygen into the combustion space,

vgravity actuated means connected to each gate member and designed and constructed to cause said gate member to resist the passage of ashes with a'variable force, and

manually operable means for simultaneouslyYY moving all of said gate members eitherV to Y closed or opened position.V

In testimony whereof ax my signature.`

LEBRECHT STEINMLLER; 

